docs: def chromsizes(self, uid):
          """
          Return the chromosome sizes from the given filename
          """
          url = "http://{host}:{port}/api/v1/chrom-sizes/?id={uid}".format(
              host=self.host, port=self.port, uid=uid
          )
  
          req = requests.get(url)
          if req.status_code != 200:
              raise ServerError("Error fetching chromsizes:", req.content)
  
          return req.content